Internally-fired engine.



No. 723,502. PATENTED MAILZI, 1903.

E. THOMSON. INTERNALLY FIRED ENGINE.

APPLICATION FILED FEB. 28, 1 898.

.2 SHEETSSHEET 1.

N0 MODEL.

No. 723,502 PATENTED MAR. 24,1903.

E. THOMSON. INTERNALLY FIRED ENGINE. APPLIOATIQN rump r213. 28. 1898.

2 SHEETS-SHEET. 2

N0 MODEL.

, valve.

or interior furnace,so to speak. After the' .Figsgt', 5, 6, and 7 are details UNITED STATES.

PATENT OFFICE.

ELIHU THOMSON, OF SWAMPSCOTT, MASSACHUSETTS.

lNTER NA LLY-FlRE D ENGINE. H

SPECIFICATION forming part Of Letters Patent No. 723,502, dated March Application filed February 28, 1898. Serial No. 671,963- tNo model.)

To all whom it may concern: I I Be it known that. I, ELIHU THOMSON, a citizen of the United States, residing in the town of Swampscott, county of Essex, and State of Massachusetts, have invented a new and usefulImprovementin Internally-Fired Engines, of which the following is a specification.

This invention relates to an improvement in internally fired engines, the object of which is to simplify the production of power from burning fuel and to enable an engine to be constructed which shall burn different kinds of fuel without change of type. I may use in my invention either liquid fuel or gas or oil vapor or solid fuel,'such as carbonaceous material. I provide a moving piston which on the forward stroke, forexample, takes in a charge of air through an inletvalve opened during the intake. The cylinder'being thus openedand filled with air, the return of the piston compresses the air into a space back of the cylinder and through a This space is adjacent to a fire-body piston has finished the compression of the air on the compression-stroke communication is shut off from the compression-space to the cylinder by the closing of the valve, and the airon expanding returns to the cylinder during the power-strokethrough the furnace or fire-pot, in which it meets the combustible and is highly heated by theheat of combustion. -Its original volume then becomes increased for any given pressure and the piston is driven forward.- Finally the gasis driven out of the cylinder in an expanded or cooled state, due to expansion by the return of the piston and the opening of the exhaustvalve made at the same time. 4

Reference is had'to the accompanying fig= ures, which show an engine'embodying'my invention. 7

Figure 1 is-a side elevation of an engine, partlyin section. Fig.2 is a plan View ofthe same. Fig. 3 is an end view or end elevation.

bustion-chamber or fire box. I

Mounted on a suitable base is a main shaft X, Figs. '1 and 2, having a crank for the coup ling of the connecting rod'R o that piston I may operate or be operated on during the rotation" ofxthe dri'vingor fly. wheel Pisfor which is at I, whereby air may be taken in. The exhaust-valve is at E, whereby the gases may be exhausted through proper passages. There is a third valve'A, which opens ton P moves in a cylinder 0, the inlet-valve a-passage or'cominunication between the cylinder-spaee 0 back of the piston P, and a lined with refractory non-conducting material and filled with granules, whereby the combustible matter is brought in contact over extended surfaces with the air from K during the power-stroke, vapor-pum p O dischargescombustible liquid,

I gas, or vaporin to the interior-refractory filling of'the fire-box F, which has perforated slabs separating it from K and from the cylinder space (3 A cam-she ft or other suitable means for operating valves I, A, and E, as well as ;the'fuel-pump 0, is provided. Thus the shaft X may be suitably geared to the main shaft X and revolve at such a rate as to allow cams L L L to give the motion of opening and shutting tothe vvalves in any'usual manner. As this is not an essential feature of the present invention the mechanism shown and a suitable oil-pump'or is used mainly as suggesting the opening and closure at vproper intervals. In the same way the pump 0 simply typifies a fuel-supply of aregulated amount to thefire-box F. This may be supplied in any way-such as by a reservoir under pressure, by a pump, by gravnecessary'that the requisite quantity be supplied to F whilethe engine is at-work. The relation of the parts may be seen in the plan Fig. 2, assisted by the end elevatien Fig. 3, where when possible similar parts are repfor same parts.

resented by similar letters found in Fig. 1

-.The manner of operation is. as follows ity, or in any way convenient--it being only Assuming all valves closed at the start, the

piston P inward, the valve 1 is opened by cam L :The piston P moves forward, drawing in air. This continues to the end of the intakestroke. .Va1ve I now shuts. val eATwide, and on the return of piston P theair before drawn in is forced freely 0am L opens through valve-opening at Ainto space K, the capacity of whichis such with other clearances as to givea predetermined compressionpressure. Valve A is now allowed to shut by 5 cam L and the forward motion of thepiston' P or power-stroke-begins, the air compressed in K being unable to get back to the space back 05 the piston, which is increasing, flows through the fire-pot F, and there meets the finely-divided and spread-out fuel within the pot and burns the fuel, assuming, of course, that the lire-pot has been previously brought to a high temperature. The flame and prodnets of combustion shoot forward into the cyljinder. This flow continues during the outward motion of the piston during the stroke,

and the increase of volume of the air whichv had been compitessedby the high temperature which it has acquired gives the power on ex-. The exhaust-valve F. now opens pension. I and thepistonPreturns,drivingoutthewaste gases or products of combustion. I To start the engine, the gas or vapor fed at 0 may be so highly superheated by passage 5 air it will fire. This, however, need only be temporarily done,-for as soon as the firing of F reaches a hightemperatureits interior combustion is produced without intermission.

scale, and in this case the gas, vapor, or oil is indicated as being pumped into what virtuallycoustitutes hollow'grate-bars G in the lire-space. .These are tubes having perforations seen in plan Fig. ,5, which are branched from a common supply S fed by the fuelpump or other means. Thespace within the refractory lining of F (indicated in the figure),

.. is, of course, filled with granules, such as 40 broken fire-brick or speciallynnolded pieces of refractory material of such size as not to fall through the spaces between the tubes G, forming the grate of the inclosure. The object of. the arrangement (lie to distribute the 5 fuel, gas, or vapor over; the whole area of the fire-box, and thereby prevent its being conceutrated'and badly mixed with the air. The openingsshown at Q are for the passage of the hot products of combustion forward into the cylinder-space and are shown as openings in the lining of F, which is of course'refractory. I

In Figs. (Sand 7 there is shown the feeding of solid fuel. In this case a hopper N is filled with specially-molded pieces of solid carbonaceous fuel, and by the rotation of the plug D steadily these pieces are received in a groove in one sideof the plug Dand carried around and dropped into the fire-space in F, where they rest in a heap upon the perforated grate or grill G If, however, the liring-space'in F is filled already, the pieces of fuel fail to feed and the rotation of theplug D does not discharge any of them. as they have shrunk within the fire-space F the arrangement begins to feed. If the fit between the plug Dand its casing issufiithrough a hot tube that on the contact of the;

In Fig. 4 the fire-pot is shown on-a larger As soon, however,

ciently tight, there will be no danger of gas escaping during the process of feeding. In

this case the solid fuel itself is burned instead of the vapor fed in as in the former figures.

The aircompressed in the space K- underneath the fire-box passes up through the furnace to the mass of. fuel and the oxygen combines with the combustible,-keeping up the fire in the fire-pot F in the same way as described in connectionIwith Fig. 1 when gas or vapor is used. The fuel particles fed in by the feeding-plug D may, of course, be granules of carbon such as compressed coke or specially-molded pieces having regularity of form, the constituent being mainly carbon.--

Waste gases are by the'exhaust-valve and air for burning fuel taken in likewise, as in Fig. 1:, the only difference being in the use of the solid fuel fed into the fire-bdx instead of liquid, gas, or vapor.

To start the action in F, Fig. 6, requires of course that at the first the mass of fuel shall be hot-enough to burn in contact with air. This may be accomplished by heating separately a mass of the fuel-granules and quickly passing them into the fire-box F either through the opening in which the plug D is placed and revolved or through a separate opening afterward closed by a tight-fitting cover.

What I claim as new, and desire to secure by Letters Patent of the United States, i s-'-.

1. In an internally-fired engine, the combination of a cylinder, a fire-space which com municates with the cylinder'through a passage that is always open, a piston arranged to draw in a charge of air on its forward stroke, a valve controlling the admission of the charge, means for closing said valve on the compression-stroke of the piston, a compressed air compartment communicating with the cylinder-space, means for interrupting the communication between the compartment and the cylinder-space on the second or power stroke of the piston, whereby the com; pressed charge of air-is sent through the firespace on its, return to the cylinder space, meansfor supplying fuel to said fire-space,-

discharged, as in Fig. 1,

and means for exhausting the return charges von the second return stroke of the piston.

' 2. In an internally=fired engine, the com I bination of a pist0n,a cylinder, a compartmentwhich is in communication with the cylinder-space through a passage which is al ways open, a second compartment which is in communication with the first compartment through a passage which is always open, and

with the cylinderspace through a valve-passage,'a valve for opening-and closing the said passage between the second compartment and the cylinder-space, valve open during and closing it during the power-stroke, and mechanism for supplyingthe fuel to the firstmentioned compartment.

means for holding the the compression-stroke,

3. In an internally-fired engine, the combination of a piston, a cylinder, a fire-chamher which is in communication with the compression-chamber through a passage, means,

such as a pump, for supplying fuel to the fire-chamber, an air-compression chamber 5 adjacent to the fire-chamber, a valve between the compression-chamber and the cylinderspace, and mechanism for closing the valve during the power-stroke. v

, 4, In an internally-fired engine, the comto 'bination of a cylinder, a piston moving therein, a valve for admitting air to the cylinder when the piston moves forward, a compressedair chamber, a valved passage connecting the chamber with the cylinder-space, means for i 5 keeping the valve openduring the com pression-astroke, a flre-chamber'iwhich-is in communication with the cylinder-space through a passage, and with the air-chamber through .engine, of a cylinder,

a passage which is always open, an exhaustvalve,and mechanism for operating the valves.

5. The combination, in an internally-fired a piston, a chamber lined with refractory material, said chamher being in communication with the cylinder-space through a passage which is always open, a second chamber for receiving the compressed air which is always'in communication with the first-mentioned chamber, and a valve located between the compressed-air chamber and the cylinder-space.

hand this 25th day of February, 1898.-

. ELIHU THOMSON. -Witnesses2 I D'UGALL) MCKILLOP, HENRY O. WESTENDARP,

- p b In witness whereof I have hereunto'set my 1 v 

